This domain is found in proteins involved in biosynthesis of molybdopterin cofactor however the exact molecular function of this domain is uncertain. The structure of this domain is known [1] and forms an incomplete beta barrel.

1: The crystal structure of Escherichia coli MoeA and its relationship to the multifunctional protein gephyrin. Xiang S, Nichols J, Rajagopalan KV, Schindelin H; Structure 2001;9:299-310. PMID:11525167